Seating a bullet .165 off the lands?

Tex S · December 1, 2013, 07:28 PM

Trying to develop a load for my 270 win using a Barnes 95gr TTSX. Barnes load data lists a col of 3.100. I have a hornady oal gauge, and after doing a big of quick math I have found that if I use the 3.100 I would be .165 off the lands in my rifle.

I know the Barnes bullets need to be set back kinda far, but this seemed excessive. I am concerned however, since I have never seen a discrepancy in col this bad.

Any thoughts?

steve4102 · December 1, 2013, 07:51 PM

If you have "The" gauge, ignore the manuals. They mean nothing to the handloader with a gauge. Seat your bullets so you have adequate neck tension and carry on.

Rule of thumb is seat at least one bullet diameter into the case. In your case that would be roughly .277 inches into the case.

.284 · December 2, 2013, 02:09 PM

Steve is absolutely spot on. I would make sure the bullet is seated deep enough in the neck as he mentioned. Beyond that, Barnes bullets like to be somewhere between .030 to .070 from the lands. If you can make them work, those TTSX bullets are quality. Good luck.

Brian Pfleuger · December 2, 2013, 02:30 PM

Concur.

I suggest following Barnes OAL data generically because Barnes bullets tend to be shorter in front of the ogive than similar bullets so if you load then to "normal" OAL you are often jammed in the rifling.

The comparator negates that concern.

Barnes bullets don't need any extra jump either. The produce slightly higher pressures with the same load compared to an "ordinary" bullet but giving them extra run doesn't change anything.

I seat them 0.050 off rifling.

.284 · December 3, 2013, 06:22 AM

Tex, here's what experimenting with the seating depth can do with the TTSX bullets.

http://thefiringline.com/forums/showthread.php?t=516111

old roper · December 3, 2013, 09:05 AM

This is from Barnes site on seating depth

Because TSX Bullets are all-copper, they have different pressure characteristics compared to conventional jacketed bullets. In our lab, we have experienced best pressures and accuracy when TSX Bullets are seated .030″ – .070″ off the lands (the grooves or rifling in a barrel.) The majority of the time, we’ve seen optimum accuracy when bullets are seated .050″ off the lands, so start there. Then move backward or forward in .005″ – .010″ increments to find the “sweet spot” for your particular rifle.

As Brian mention bullet comparator does help and I start mine at .050" off and most time that's were I get the best accuracy.

Well good luck

December 1, 2013, 07:28 PM	#1
Tex S Senior Member Join Date: November 12, 2008 Location: Fort Worth, TEXAS Posts: 909	Seating a bullet .165 off the lands? Trying to develop a load for my 270 win using a Barnes 95gr TTSX. Barnes load data lists a col of 3.100. I have a hornady oal gauge, and after doing a big of quick math I have found that if I use the 3.100 I would be .165 off the lands in my rifle. I know the Barnes bullets need to be set back kinda far, but this seemed excessive. I am concerned however, since I have never seen a discrepancy in col this bad. Any thoughts?

December 2, 2013, 02:09 PM	#3
.284 Senior Member Join Date: July 8, 2009 Location: davison, michigan Posts: 665	Steve is absolutely spot on. I would make sure the bullet is seated deep enough in the neck as he mentioned. Beyond that, Barnes bullets like to be somewhere between .030 to .070 from the lands. If you can make them work, those TTSX bullets are quality. Good luck. __________________ Guns have only two enemies, rust and politicians! Deer are amazing creatures....so please don't burn the sauteed onions and I'll pass on the steak sauce, thank you.

December 2, 2013, 02:30 PM	#4
Brian Pfleuger Moderator Emeritus Join Date: June 25, 2008 Location: Austin, CO Posts: 19,578	Seating a bullet .165 off the lands? Concur. I suggest following Barnes OAL data generically because Barnes bullets tend to be shorter in front of the ogive than similar bullets so if you load then to "normal" OAL you are often jammed in the rifling. The comparator negates that concern. Barnes bullets don't need any extra jump either. The produce slightly higher pressures with the same load compared to an "ordinary" bullet but giving them extra run doesn't change anything. I seat them 0.050 off rifling.

December 3, 2013, 06:22 AM	#5
.284 Senior Member Join Date: July 8, 2009 Location: davison, michigan Posts: 665	Tex, here's what experimenting with the seating depth can do with the TTSX bullets. http://thefiringline.com/forums/showthread.php?t=516111 __________________ Guns have only two enemies, rust and politicians! Deer are amazing creatures....so please don't burn the sauteed onions and I'll pass on the steak sauce, thank you.

December 3, 2013, 09:05 AM	#6
old roper Senior Member Join Date: June 11, 2007 Posts: 2,155	This is from Barnes site on seating depth Because TSX Bullets are all-copper, they have different pressure characteristics compared to conventional jacketed bullets. In our lab, we have experienced best pressures and accuracy when TSX Bullets are seated .030″ – .070″ off the lands (the grooves or rifling in a barrel.) The majority of the time, we’ve seen optimum accuracy when bullets are seated .050″ off the lands, so start there. Then move backward or forward in .005″ – .010″ increments to find the “sweet spot” for your particular rifle. As Brian mention bullet comparator does help and I start mine at .050" off and most time that's were I get the best accuracy. Well good luck __________________ Semper Fi Vietnam 1965 VFW Life member NRA Life Member

December 1, 2013, 07:51 PM	#2
steve4102 Senior Member Join Date: December 23, 2005 Location: Minnesota Posts: 2,952	If you have "The" gauge, ignore the manuals. They mean nothing to the handloader with a gauge. Seat your bullets so you have adequate neck tension and carry on. Rule of thumb is seat at least one bullet diameter into the case. In your case that would be roughly .277 inches into the case.